Check out
Virtual hosting in Europe
Are you looking for high quality, fully customizable virtual hosting in central Europe? We can offer good prices, quality support, modern datacenters and much more. Check out our Virtual hosting in Europe.
Search
Calendar
| Mo | Tu | We | Th | Fr | Sa | Su |
|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | ||
| 6 | 7 | 8 | 9 | 10 | 11 | 12 |
| 13 | 14 | 15 | 16 | 17 | 18 | 19 |
| 20 | 21 | 22 | 23 | 24 | 25 | 26 |
| 27 | 28 | 29 | ||||
Navigation
Volcanoes Key To Earth's Oxygen Atmosphere
3. 9 2007 (17:00)
A switch from predominantly undersea volcanoes to a mix of undersea and terrestrial ones shifted the Earth's atmosphere from devoid of oxygen to one with free oxygen, according to geologists. Before 2.5 billion years ago, the Earth's atmosphere lacked oxygen. However, biomarkers in rocks 200 million years older than that period, show oxygen-producing cyanobacteria released oxygen at the same levels as today. The oxygen produced then, had to be going somewhere.
